Apparatus for determining a coagulation factor of blood samples



4, 1975'2 J. SCHILLING ETAL APPARATUS F OR DETERMINING A COAGULATIONFACTOR OF BLOOD SAMPLES Fm Nov. 25. 1950 INVEN TOR. J red Jf's'chizzz ny and .Hlberifle zz't'ale xrnwnbvpiluiiilil Patented Nov. 4, 1952APPARATUS FOR DETERMI NING A COAGU- LATION FACTOR OF BLOOD SAMPLES FredJ. Schilling, New York, and Albert De Natale,

' Bayside, N. Y.

Application November 25, 1950, Serial No, 197,552.

3 Claims. (01. 23-453) This invention relates to a new and improvedmethod and apparatus to permit the physician at the bedside of a patientto quickly and easily determine a coagulation factor of blood taken fromthe patient in cases where the patient may be suffering from blood clotconditions of one form or another. e e In accordance to previousprocedures with patients suffering from these conditions, the well knownprothror'nbin test has been employed to determine a coagulation factorof the patients blood of which samples have been extracted. The onlydifficulty with this test is that it generally is required that thesamples thus obtained have to be processed in conformity with this wellknown test in a laboratory where there is the necessary equipment. Thisnaturally has involved the expenditure of time, and in some cases thistime factor has been exceedingly important where the condition of thepatient called for a much more rapid determination than has hithertobeen available.

The determination of this coagulation factor which relates to the natureof the blood of the patient, and the time it takes to coagulate, is avery important factor to determine prior to the administration to thepatient of certain anticoagulation drugs such as Dicumarol and/orTromexan. V

The main object of this invention is to pro vide a simple and eflicientand rapid method and apparatus whereby the physician at the bedside ofthe patient may take samples of his blood and quickly and easily processthe blood to determine the coagulation time factor there rapidly andeasily.

A further object is to provide a simple device in the form of a tube,preferably L -sha'pe, of glass or similar material which is closed at anopen end with a hermetically sealedcover, such as rubber, which ispenetrable and contains a predetermined quantity of coagulant such asstable thromboplastin in dry powdered form.

This tube, with the powdered coagulant therein forms partof a kit whichthe physician may take with him to the bedside of the patient. Tocomplete this kit, there is provided a small vial in which is disposed aquantity of diluent and the vial is sealed off by a penetrable rubberstopper. With this vial there is provided a special needle soconstructed that it may penetrate the stopper only to a predeterminedextent. This needle is hollow and open at both ends and, after it hasbeen inserted into the vial, the vial and the needle are inverted andthe other end of the needle inserted through the hermetic seal on theabove mentioned tube so that a predetermined amount of diluent may bedrawn into the tube by reason of the vacuum therein.

'- -An ordinary pipette is then employed to draw a predetermined amountof blood from the patient and before the pipette is so employed it isrinsed in any suitable manner by a sodium oxalate solution. When theblood sample is thus in the pipette the seal of the tube is taken offand the blood sample is blown into the tube to mix with the coagulantwhich is now in liquid form. From the moment the blood is introduced,the tube is grasped in the hand and spun back and forth to mix theelements therein and until the blood starts to coagulate. From themoment of bloodintroduction a stop watch is started so that the exacttime it takes to coagulate the blood in this manner may be noted. Thismanipulation of the tube in the hand of the physician is performed atroom temperature which is noted.

It will therefore be seen that we have provided a simple method whichcomprises the disposition in a hermetically sealed tube of apredetermined quantity of a coagulant in stable form, the ,introductioninto the tube of a predetermined quantity of diluent by penetration. ofthe seal, followed by the introduction of a definite quantity'of bloodsample after which the tube is rapidly spun in the hand at roomtemperature and under accurate notation of the time consumed from theintroduction of the blood Lmtil it coagulates. This simple method may beemployed at the bedside or in the doctors office and does not requirereference to a laboratory with the consequent loss of time in making-thenecessary determination, upon which depends the application of theproper anti-coagulation drug.

Merely for the purpose of illustration, a preferred form of theapparatus employed in practicing this. invention is shown in thedrawings, of which:

Fig. 1 is a side elevation of the hermetically sealed tube containing apowdered coagulant;

Fig. 2 is a general side view of the tube shown in Fig. l with portionsbroken away and showing associated therewith a diluent vial; I

Fig. 2A is a detail showing a special needle used in connection with thediluent vial for the introduction of diluent into the tube; and,

Fig. 3 is a section showing the tube with the coagulant, the diluent,and the blood sample therein.

Referring now merely to the specific form of the apparatus shown in thedrawings, which is employed to make effective this new method ofdetermining coagulation, time factors of blood, it will be seen that oneelement of the apparatus comprises a tube, preferably of glass, andofL-shape, having a vertical leg l0 open 'at its upper end, a connectedlower horizontal leg H. and a sealing cap l2, preferably of rubber,whereby the tube may be hermetically sealed and a predetermined vacuumestablished therein.

Another element of the apparatus is a glass vial I3 adapted to containany suitable diluent l3" such as distilled water. The open end of thisvial is closed, preferably by a rubber stopper l4.

stopper H! on the vial l3.

Before the tube above mentioned is hermetically sealed oiT, apredetermined amount of coagulant l5 in dry powdered form is disposedtherein. This coagulant is preferably thromboplastin, which in this formis stable, whereas in solution it is unstable.

Another element of the apparatus is a special needle shown in Fig. 2-Awhich is in the form of a hollow capillary tube l6 open at each end, andwith the ends beveled to facilitate penetration. This needle,intermediate at length, is provided with an enlarged portion 1 I orsimilar element to act as a stop or abutment as and for the purposes tobe described. It is to be clearly understood that this enlargement maytake otherforms, but in the form shown it is an enlarged bead on theoutside of the needle and does not obstruct the. passage through theneedle from one end to the other of any fluid. The only other elementwhich is used in connection with this novel procedure is an ordinarypipette used for the purpose of drawing the predetermined amounts ofblood into it from the patient for the purposes hereinafter set forthand not shown, since it is a well known device.

With these elements of the apparatus provided in a suitable kit or case,the physician has, ready athand simple means for an accurate, quick, andeasy determination of the coagulation factor of the patient whether thepatient is seated in his ofiice, or the physician is at the bedside ofthe patient, and this determination can be effected without thenecessity of referring to a laboratory, which involves loss of time andadded expense. In employing the above apparatus, the physician firsttakes the needle shown in Fig. 2-A and thrusts one end of it through theHe then inverts the vial with the needle thus disposed and projects theother end of the needle l6 through the seal I? on the tube containingthe stable coagulant. The capillary structure of the needle [6 willprevent diluent from flowing out of the vial even when the vial isinverted until the needle has been projected through the seal l3,whereupon the influence of a vacuum in the tube will cause a definiteamount of diluent to be drawn out of the vial into the tube to mix withthe coagulant powder l5. It will be, of course, clear that the stopmember or exterior enlargement intermediate the length of the needle ['1will limit penetration of the needle into the stopper M and, through theseal 12.

The next step taken by the physician is to prepare a desired surface ofthe skin of the patient in any well known manner prior to the extractionof a blood sample. He then takes the usual pipette with the flexiblerubber tubing connected to one end to be placed in his mouth and then,as a preliminary step, sucks up into the pipette a small amount ofsodium oxalate solution in order to thoroughly rinse the interiorsurface of the pipette. This is. done to prevent the blood drawn intothe pipette from starting to coagulate in the pipette. The rinsedpipette is then used in the regular manner and is, as usual, calibratedon its exterior surface so that a predetermined amount of blood may bedrawn up into it.

Just prior to this step. of taking the blood sample from. the patient,the. vial l3 and the seal [2 are removed from the tube containing thecoagulant. now in solution, and the blood sample is blown into the tubefrom the pipette. At this instant. of time, the physician grasps theupper end of the tube. and starts to spin it back and forth in his hand,while at the same time starting a stop watch so that accuratemeasurement of the time it takes the blood in the tube to coagulate maybe measured. All these steps are conducted at ordinary room temperatureand permits this time factor to be quickly and easily determined,whereby based on the value of the time factor, the desired dose ofanti-coagulation drug can then be selected. In many conditions andcircumstances where time is. of the essence, this accurate, rapid, andeasy method, and the simple apparatus employed may well be of extremeimportance.

While the invention has been described in detail and shown with respectto the accompanying drawings, it is not to be limited to such details,since many changes and modifications maybe made in the invention withoutdeparting from the spirit and scope thereof. Hence, it is desired tocover any andall forms and modifications of the invention which may comewithin the language and scope of any one or more of the appended claims.

We claim:

1. A kit for determining the coagulation time factor of blood including,in combination, an L-shaped vial having an opening at the top thereof, apenetrable closure disposed over said opening, a second vial having anopening and a penetrable closure disposed thereover and being adapted tocontain a liquid, and a needle having a capillary passage, said needledetachably connecting said vial by insertion through said penetrableclosures so that the liquid may flow from the second vial to theL-shaped vial, said, L-shaped vial being adapted for oscillatablerotation when detached from said needle.

2. A kit for determining the coagulation time factor of blood including,in combination, a vial having a body portion, an outwardly extendingportion at the bottom of said body portion, and an opening at the top ofsaid body portion, a penetrable closure disposed over saidopening, asecond. vial having an opening and a penetrable closure disposed oversaid opening, anda capillary needle inserted through each closure so asto connect said vials, said first mentioned vial being detachable fromsaid needle and adapted to. receive a coagulating material, a diluent,and blood.

3. The combination with a vial having a penetrable closure and a.capillary needle. adapted for insertion through said closure, of anL-shaped vial, having an opening atone end and a penetrable closuredisposed over said opening, said L-shaped' vial, being detachablyconnected to said first mentioned vial by means of. said needle andbeing designed for oscillatable rotation.

FRED J. SCHIILING. ALBERT DE NATALE.

REFERENCES CITED The following references-are. of record in the file ofthis. patent:

Wintrobe, Clinical Hematology, 2d ed., Lea and Febiger, Philadelphia,April 19, i949, pages 207-208.

Sou-ter and- Hark, Quicks Prothrombin Test Simplified by theUse'ofStable Thromboplastin, Am. Four. Med. Sci. 200, page 603 (1940-) How toMake Standard Volumetric Solutions in a Few Minutes, E. H. Sargent &Co., Chicago, 111.. March 31, 1947:, 4' pages.

1. A KIT FOR DETERMINING THE COAGULATION TIME FACTOR OF BLOOD INCLUDING,IN COMBINATION, AN L-SHAPED VIAL HAVING AN OPENING AT THE TOP THEREOF, APENETRABLE CLOSURE DISPOSED OVER SAID OPENING, A SECOND VIAL HAVING ANOPENING AND A PENETRABLE CLOSURE DISPOSED THEREOVER AND BEING ADAPTED TOCONTAIN A LIQUID, AND A NEEDLE HAVING A CAPILLARY PASSAGE, SAID NEEDLEDETACH-